1. Field of the Invention
This invention relates to a semi-finished product for the manufacture of a closable opening device for a sealed packaging, which contains a pourable medium, wherein the device includes a pour-out spout with a flange, a cylindrical cutting element with an upper edge defining a plane surface, the lower edge having one or more teeth, and an inner skirt surface with catches which act in the radial direction and which cooperate with catches on the inner side of the cover surface in a screw cap.
2. Discussion of Related Art
A closable opening device of the initially mentioned type is known from European Patent Reference EP-A-1088764, which applies a principle generally common with closure technology, that multipart closures are manufactured so that two parts are arranged above one another and are injected as one piece, connected to one another via breakage locations. An effort with regard to tooling is reduced and the assembly is simplified, because the parts which are connected to one another via breakage locations are arranged to one another already in their exactly aligned relative position and thus only need to be pushed together. With the solution known from the prior art, the semi-finished product is only of a connection of a pour-out spout to a flange together with a cylindrical cutting element. The combination of a semi-finished product for the manufacture of a closable opening device as described further above, with which not only the pour-out spout is manufactured as one piece not only connected to the cutting element, but also to a screw cap, has not been considered as possible by the people skilled in the art. The reason for this consideration is that one has always assumed that all parts connected to one another should be connected to one another in the correct position for the final assembly, in order to have the required usefulness.
Under these preconditions however, all three parts may not be manufactured in a single-piece semi-finished product because the inner diameters of the three parts are different and the screw cap is closed on one side. In the position which is correct for assembly the cutting element with its smallest inner diameter would be at the very bottom and thus, above this, the pour-out spout with its flange, and in turn, above this, the screw cap whose inner diameter is the largest. With this arrangement however, the core of the tool may not be pulled out of such a semi-finished product. Were the screw cap only a cylindrical element open on both sides, then this would be possible, but this is not the case. For this reason, in the state of the art, only the manufacture of a semi-finished product is known, with which the cutting element is manufactured as one piece with the pour-out spout. Such a semi-finished product is known from European Patent References EP-A-1088764 and EP-A-1084060.